My understanding of red push is that it's a colour decoder misalignment that can come from oversaturation but more likely from excessive intensity. That's why people can get perfect primary chromaticities on CIE diagrams and yet still see red push... because intensity is not recorded on the chart.
Now with your first graph it appears that you are still only adjusting saturation (forgive me if I'm wrong as I'm not familiar with HCFR at this moment) albeit across 4 points, but as you no longer see any red push (I take it there was some pre-calibration) the logical explanation would be that your intensity was correct from the outset, or was corrected either purposely or coincidentally with the CMS control adjustments.
Which brings us to the second graph which – if it is what I think it is – plots luminance/ intensity at different saturation points. If anything your red is less intense compared to reference between 0% to 75%, which will again explain the absence of red push.
That's a good point actually - I haven't really experimented to see how the luminance affects things - I had only been going by the saturation graph when making my adjustments, as I don't have brightness controls per colour on the '68. My guess is that they are now using a new CMS system that doesn't offer these controls for whatever reason. As the set has features such as 100Hz, I wouldn't be expecting it to be a downgraded version of the controls on the '66 or C3030D anyway.
If anything it means that, while there is the right amount of red in the image (saturation is good) the lower intensity of the reds may mean things actually appear under-saturated now. Either way it certainly explains the lack of a red-push on my TV.
As it's a regular LCD, I wasn't expecting great reds anyway - but I'll take that over an extended gamut display any day, personally. I don't see why Sony/Samsung are focusing on going past Rec.709 so much.
But top class info there andrewfee, this ingenious technique and software may well empower us with objective measurements rather than bleed-prone filters and subjective eyeballing for colour decoding alignment... I shall try them out and report back. 
Many thanks again.
No problem.
I'm just another hobbyist that's learning all of this through trial & error and reading up about it (I have spent a
lot of time going over things though) so what I'm saying may not be 100% correct however it's certainly something to look into anyway, and has provided much more pleasing results than using colour filters to adjust things ever has.
Hopefully it will provide you with another way to rate these displays more objectively, rather than just rating them on what "looks good to me." Not that I don't value your opinions - the reviews on this site are by far the best I've seen anywhere. I wish it was around (or that I had known about it, if it was) the last year or two, as I've gone through about 10 HDTVs (mostly LCD though, as I'm a gamer) trying to find something I was happy with. In the end I was fed up, and as the WLT68 didn't appear to be doing anything particularly wrong - good motion handling for an LCD, reasonable colour reproduction, decent scaling, and a lack of edge enhancement without being too soft, I ended keeping it. As I'm using HD more and more now though, I'm looking to get something larger (hopefully around 50") and with better black levels. (which wouldn't be hard, as I'm sure you'll know from having seen other Toshibas!) At the time I bought it, black levels weren't a concern as it was being used in a fairly bright room, but I now try to have things as dark as possible.
P.S. Of course, since you're so obsessive about colour reproduction, you do realise that you need a display unit that's capable of D65 greyscale across most intensities... I wonder how did your WLT68 fare?
The greyscale is definitely not as smooth as I would have liked, particularly at 50% IRE where there is a sudden dip in blue (about 5-10%) that I haven't been able to get rid of, and then below about 20% blue starts to peak quite significantly. (about + 10-20% if memory serves correctly) It's not as bad as I have seen on some LCDs, but it's certainly not as good as the BRAVIAs, for example. Gamma isn't so hot either, but again, I've seen a lot worse on other LCDs. This was really just something to hold me over until something better came out.
This is another reason I'm looking into plasmas again though - I hope to sell my WLT68 soon, and will be holding out for the 8G Pioneers which sound like a great option for me, particularly with their reputation for colour reproduction. (and now that they apparently have solved their black level problems)
My only real concern is that I spend a lot of time gaming, and am still worried about burn-in/retention - I know most people say it's no longer an issue, but I can sometimes spend four hours or more playing the one game without realising it, which is a lot of time with a static HUD onscreen. I would be keeping contrast quite low though, as I like to have white at 120cd/m2 max in a dark room - anything else is blinding, in my opinion. What concerns me the most are the green phosphor trails though - I found them totally unbearable on the Panasonic Plasma I bought earlier this year (TH37PD60 I think? The "SD" model) as they were very obvious with games, and had to return it due to this. (LCD's smearing is a lot less objectionable, in my opinion, even though I would like better sharpnes with motion)
